JSP vs FMJ and Lead Deposits

[aaaaa]

I am pretty new to guns and ammo other than shotguns. For target practice I was going with Full Metal Jacket (FMJ) to avoid lead deposits. But now I see how the FMJs are put together and am thinking that jacketed soft points (JSP) actually may be even better at preventing leading of the barrel. Here is what I read that leads me to this thought:

A soft-point bullet is essentially a full metal jacket bullet, which has a lead core wrapped in a hard copper casing, with the lead tip exposed at the nose of the bullet. To make a full metal jacket, the copper shell or “cup” of the bullet is made with an opening at the bottom, allowing lead to be poured inside. Because of the manufacturing process, full metal jackets usually have exposed lead at the rear.

https://www.ammunitiontogo.com/lodge/what-are-soft-point-bullets/

Does it really make any difference? Or is it really just a matter of avoiding unjacketed lead bullets?

Even if it makes no difference for preventing lead deposits, JSP seems a better choice in that it also is great self defense ammo:

...soft points expand more than full metal jackets and penetrate better than hollow points. They have a wide array of uses from hunting large game, to hunting small game, to target shooting.

https://firsttimegunbuyer.com/ammo-types/bullet-types/soft-point-bullets.php

 

[Leon tP]

What are you shooting? What kind of pistol/handgun? Do you hunt? Is it for Self Defense? Are you only concerned about lead deposits?

Here's the short, short version.

Neither FMJ or JSP will "lead" up your gun. If you need/want penetration use a solid like your FMJ. If you want expansion use a Hollow Point. If you want expansion but believe (or know) that a certain application will result in HP over expansion (less penetration), use a Soft Point. For handgun use, Soft Point bullets are more often (but not always) found in hunting applications.

Here's a basic primer to get things started.
https://gunnewsdaily.com/bullets-guide/

 

[JohnKSa]

I've never had any leading issues from shooting jacketed rounds.

JSP is probably not "great" self-defense ammo--but it might be better than FMJ if it expands. More suited to hunting game that's large enough that deep penetration is favored over extreme expansion.

 

[BlueHeelerFl]

Out of handguns most JSP ammo will not expand enough to be useful in a self defense shooting. They are better suiting for hunting.

That being said a 357 mag SJP will expand nicely from a 16" or longer barrel in a self dense situation.

Lucky Gunner has a video on YouTube showing JSP ammo fired from handguns and rifles.

 

[jmr40]

Hard to give an answer to all of your questions until we know what you're shooting. I'm assuming a rifle since JSP are not that common with handgun ammo. At any rate neither will leave lead deposits in the barrel. Copper deposits maybe, and that can be just as bad.

There are pure lead bullets that are much more common in handguns and occasionally in low velocity rifle rounds. Pure lead is too soft to be fired very fast without serious leading of the barrel.

And then there is hard cast lead. It isn't jacketed but is a lead alloy that is much harder than pure lead. Those bullets can often be fired in handguns to faster velocity than jacketed bullets.

Which is best for SD depends on the cartridge and what you're trying to do.

 

[Jdague12]

I reload JSP, JHP, FMJ, and polymer bullets and I never have any fouling issues. Years ago, we’d shoot cast bullets all day long and run some jacketed bullets behind them and it got rid of majority of the fouling.

 

[buck460XVR]

Lead deposits generally come from the friction of the exposed lead to the rifling as the bullet is propelled down the barrel. Sometimes it's from hot gases escaping around the bullet. Jacketed bullets were designed to prevent lead from touching the inside of the barrel, so any jacketed bullet will prevent leading. You may tho, still get a small amount of copper fouling due to the same scenario. In revolvers, leading is sometimes found on the forcing cone due to the same process. As for terminal performance of different types of bullets, it come down to the intended usage. As has been said FMJs have little or no expansion when used against body tissue, whether human or animal. JSPs generally have controlled expansion with the intent of keeping the bullet intact and retaining most of the original bullet weight, along with giving deep penetration. JHPs generally have less controlled expansion and are designed to dump most of their energy in the target, resulting in massive expansion with less regard to penetration and weight retention. But those are general assumptions. How the bullet is constructed, has as much to do with expansion and energy dumping as the type of bullet. Most reputable bullet makers will give good claims as to what to expect and what the intended purpose of the bullet is(hunting, HD/SD, target, etc). Plated bullets are just solid lead bullets encased in a very thin layer of copper/gilding metal in order to prevent leading. Same is true with powder coated lead bullets.

 

[aaaaa]

I figured the bullet differences was a broader discussion but I might better have put this in the handgun forum. Anyway, right now this is being shot out of a 2.5-inch barrel snubby. I bought them for range practice and have hollow point for self defense. I see anyway that JSP is probably better than FMJ if you got in a pinch and had to use it in self defense. So maybe it does not matter for the range what type of bullet I shoot and I can simply buy the lowest cost (avoiding unreliable brands of course) ammo. I also have for target practice some polymer coated round points, which presumably are better for self defense than FMJ, but still not desirable for that purpose.

 

[Jdague12]

If you got in a pinch, ANY bullet works. FMJ has been standard NATO round and it has stopped MANY a bad guy. JHP are best (because that’s what they’re designed for), but in a pinch, don’t think that even a little round nose .22 won’t hurt. Most of the time, the bang is enough to send someone running and wishing they’d picked on someone else.
For someone who has never been in a situation or training, capacity is more important than the bullet itself. When the fear and stress hits, most people aren’t trained to control their shots and make them count. But yes, if you can carry JHP, carry them.
As far as target practice goes, I’m fond of the polymer bullets. Readily available and a bit cheaper

 

[CapnMac]

But now I see how the FMJs are put together

And, bullet tech has changed over the years. And not changed, too.

Heavy gilding jackets use to be used for forms for molten lead; but that was long ago. Many FMJ have a thinner jacket which is swaged around the cast lead core.

The increase in indoor ranges has seem many TMJ (Total Metal Jackets) where a gilding metal disk is on the cast core and the outer jacket swaged over the disk. Others are just plated up entire. Either way prevents lead at the base of the round potentially vaporizing and being spread inside an enclosed range. (Ammo labeled as "green" typically will have TMJ and primer s w/o lead styphanate, to address keeping lead content down indoors.)

"Leading" is not a huge issue in modern handguns unless one is running a lot of soft lead cast bullets.
Much like copper fouling is more of a rifle issue than a pistol issue.

 

[jag22]

My standard answer to questions like this is "it doesn't matter what you hit them with, it's where you hit them.
Lead is not a death sentence for a gun, it can be cleaned. Quit over thinking it.

 

[Riomouse911]

I rarely shoot jacketed bullets in revolvers, at least 90% of my shots are coated or plated lead bullets. (I shoot mostly indoors so I went away from lead-lube bullets to cut down on smoke.) Jacketed bullets work great, but cost a bunch more.

For a 2.5” barreled revolver, IMHO I’ll say save some $$ and go ahead with plain, coated or plated bullets. You should also pay for some good training and practice what’s learned.

Save the JHP for self defense.

Stay safe.

 

[aaaaa]

I rarely shoot jacketed bullets in revolvers, at least 90% of my shots are coated or plated lead bullets. (I shoot mostly indoors so I went away from lead-lube bullets to cut down on smoke.) Jacketed bullets work great, but cost a bunch more.

For a 2.5” barreled revolver, IMHO I’ll say save some $$ and go ahead with plain, coated or plated bullets. You should also pay for some good training and practice what’s learned.

Save the JHP for self defense.

Stay safe.

Yep, I recently purchased a bunch of these for the range:

 

[Riomouse911]

looks like you’re on your way .

It sounds like you’re starting to get interested more and more into shooting. Save your brass cases, it won’t be long before you buy a basic reloading setup, a manual and components and start rolling your own ammo. Hopefully things will loosen up a bit in the near future and you’ll be able to get started on your next hobby.

That’s how many, if not most, of us got started.

Stay safe.